Starlight Cascade Sky Quality Meter

Background

We were at a meeting of the NYAA
in the spring of 2005 in Toronto where
Dr. Doug Welch from McMaster University talked about measuring
light pollution using a custom built
Sky Quality Meter.
Being very interested in Responsible Lighting and Light Pollution
(RASC-KCRASCIDA
),
we purchased one, had it delivered shortly and started using it.
The "Sky Quality Meter" measures the brightness of the night sky in magnitudes per square arcsecond.
At a recent NYAA StarBQ Observing Session north of Cobourne, we tested our unit aside two others and got readings within
0.1 of each other.

In early July 2005 our unit was recalled for a calibration error and another bug that surfaced
during the beta testing, that of the exposed switch being pressed when in storage.

We've received the Mark 2 unit, returned the Mark 1 unit and have started
taking regular data.

Some of the data tables items needed are:
date, time, location, astronomical twilight time for that day, cloud
cover, and the actual three readings (within one minute to track accuracy).
Here is a Sample Data Recording Sheet in a small
adobe acrobat file.

With this data we hope to monitor the long term (years) Sky Quality (light Pollution) levels,
possible short term (local lighting changes), provide a baseline of data for our
location to compare to other locations.

Updates:

2010 Oct 16 - we find that we are not using or recording the data nearly as much
as we would like to anymore - some 5 years later. The data loggin SQM is looking
nicer and nicer.

Tips for use

Use after astronomical twilight (sun is more than 18 degrees below horizon before
sunrise or after sunset)

aim right up at zenith

note cloud conditions and moon phase and position. Ideally there will be no cloud or moon when taking readings.

References

Each of these references is printed out and carried in our 3 ring binder along with
a few dozen datarecording sheets. We also have a smaller notebook to record data when
we are away from our observatory.